Filter
Top Products
Table 18: PIM and VoIP Module Terms (continued)
DefinitionTerm
Stateless firewall filter that enables dial-on-demand routing backup when applied to
a physical ISDN interface and its dialer interface configured as a passive static route.
The passive static route has a lower priority than dynamic routes. If all dynamic routes
to an address are lost from the routing table and the router receives a packet for that
address, the dialer interface initiates an ISDN backup connection and sends the packet
over it. See also dial-on-demand routing backup; floating static route.
dialer filter
Feature that provides a J-series Services Router with full-time connectivity across an
ISDN line. When routes on a primary serial T1, E1, T3, E3, Fast Ethernet, or PPPoE
interface are lost, an ISDN dialer interface establishes a backup connection. To save
connection time costs, the Services Router drops the ISDN connection after a configured
period of inactivity. Services Router with ISDN interfaces support two types of
dial-on-demand routing backup: on-demand routing with a dialer filter and dialer
watch. See also dialer filter; dialer watch.
dial-on-demand-routing
(DDR) backup
Dial-on-demand routing (DDR) backup feature that provides reliable connectivity
without relying on a dialer filter to activate the ISDN interface. The ISDN dialer interface
monitors the existence of each route on a watch list. If all routes on the watch list are
lost from the routing table, dialer watch initiates the ISDN interface for failover
connectivity. See also dial-on-demand routing backup.
dialer watch
Ability of a Services Router with a digital subscriber line (DSL) connection that has lost
power to send a message informing the attached DSL access multiplexer (DSLAM)
that it is about to go offline.
“dying gasp” notification
Enhanced PIM. A particular type of high-speed PIM, such as the Gigabit Ethernet ePIM
or 4-port Fast Ethernet ePIM, which can be inserted only in high-speed slots (slots 3
and 6 on a J4350 Services Router, or slots 2, 3, 5, and 6 on a J6350 Services Router).
ePIM
Route with an administrative distance greater than the administrative distance of the
dynamically learned versions of the same route. The static route is used only when
the dynamic routes are no longer available. When a floating static route is configured
on an interface with a dialer filter, the interface can be used for backup.
floating static route
Interface between an ISDN network and a network termination device consisting of
two twisted pairs, one each for transmitting and receiving. The S/T interface usually
resides in the customer premises and operates at 192 Kbps, of which ISDN traffic
accounts for 144 Kbps.
ISDN S/T interface
Single twisted–pair interface line connecting the customer premises unit in an ISDN
network to the central office. A U interface runs at 144 Kbps (128 Kbps for two B
channels and 16 Kbps for the D channel).
ISDN U interface
Standard telephone service that allows limited speed and bandwidth of 52 Kbps, which
is also know as public switched telephone network (PSTN).
plain old telephone
service (POTS)
ISDN service intended for higher-bandwidth applications than ISDN BRI. ISDN PRI
consists of a single D-channel for control and signaling, plus a number of 64-Kbps
B-channels—either 23 B-channels on a T1 line or 30 B-channels on an E1 line—to
carry network traffic.
Primary Rate Interface
(PRI)
Universal switching PIM. A particular type of PIM, such as the Gigabit Ethernet uPIM,
which can be universally inserted in any slot on a J2320, J2350, J4350, or J6350
Services Router.
uPIM
PIM and VoIP Module Terms ■ 45
Chapter 3: PIM and VoIP Module Overview